Apparatus for the manufacture of hollow india-rubber balls



Sept. 11, 1923. I 1,467,438 A. LAWTON APPARATUS FOR THE MANUFACTURE OF HOLLOW INDIA RUBBER BALLS Filed June 8, 1922 2 Sheets-Sheet 1 I Sept. 11, 1923. l,467;438

A. LAWTON APPARATUS FOR THE MANUFACTURE OF HOLLOW INDIA RUBBER BALLS v Filed Jl me 8. 1922 2 Sheets-Sheet 2 2 s J 5 J 0 s 0 and so far as the apparatus is concernedfiias reference to that type referred to in British four petal'shaped plates, or plates which are rubber placed between them after which by means of lever and link mechanism, the

a pointat the upper end, the sides making stuck together that air may escape at the been cut to make air ti ht joints, after which rubber plug, projects inside the ball but its ri atented ept ll, 1923.

ALFRED LAWTON, 0F MANCHESTER, ENGLAND.

AIIARA'I'US FOR THE MANUFACTURE OF HOLLOW INDIA-RUBBEE Bihmfi.

Application filed June 8, 1922. Serial No. 566,79.

outer end is nsually completely cleared away at the time that the petal-shaped plates completely close. I have found it is desirable to do away with the rubber plug, firstly because its insertion in the. apparatus be tween the-plates is a somewhat dangerous operation owing to theliability of the operators fingers being cut by the plates as they are closing and secondly because it is found that there is also a tendency for the plug to pull away somewhat from the inner sur face of the ball during vulcanization and so disturb the joint and sometimes distort the ball out of shape or again form a somewhat rough finish at the outside of the ball,

My invention consists in so constructin the petal-shaped! plates as toform a be bulb'or like inflatable article with an improved and properl -sealed joint particularly at the point w ere the plates meet at their upper ends and I further consists in To all whom it may concern:

Be it known that I, ALFRED LAw'roN, a subject of the King of Great Britain and Ireland, and resident of Manchesten'in the county of Lancaster, England, have invented certain Improvements in and in Apparatus for the Manufacture of Hollow India-Rubber Balls, of which the following is a specification. v

This invention relates to improvements in and .in apparatus forthe manufacture of hollow balls, bulbs and like inflatable articles from india rubber and similar material,

Patent No. 13235 of 1897, the objects of my invention beingto provide an improved construction of ball,"bulb or like inflatable article and improvements in the apparatus by which such articles are manufactured.

In the specification of the aforesaid patent an apparatus is desri'bed for making a hollow india rubber ball oi the like from a fiat sheet of plastic rubber which is suitably bent, shaped and the excess material cut awa by the aforesaid apparatus. The essential feature of such apparatus comprises 7 a position within the upper ends of the petalshaped'plates and prevent itprotruding as the latter are being closed to form the joints and cut 0d the surplus material'.

My invention will be fully described with reference to the accompanying drawing which by way of example shows'apparatus, designed particularly for the production'of hollow india rubber or like balls, in which Fig. 1, is a plan of the petal-shaped plates in open position and the block to which they are pivoted; v

Fig. 2, plan showing the plates-closed; Fig. 3, sectional? elevation of the plates in open position; i

Fig. 4, plan of amodified form of the substantially quarter hollow spheres, suitably hinged at their lower ends so that the plates may be opened out and the flat sheet of plates are closed so as to bend the rubber sheet upwardly, cut.;ofi' the surplus material or corners of the sheet and at the same time join upthe edges of the sheet which have the partially-formedall is removed from the machine and vulcanized in the known Figs. 5 and 6 plan of inflated lls proway. The plates referred to each come to duced bythe devices illustrated'in Figs. 1 to 3 and Fig. 5i, respectively showing the a sharp acute angle whilst the out rubber sheet substantially corresponds to the shape of the plates along the unction lines. It therefore follows that'unless the pointed ends of the cut rubber'sheet become properly sheet are made In carrying out my invention the forecation of apparatus constructed in acordance with my invention by making two of the etal-shaped plates at (Figs. 1 and 3)' somew at smaller than usual for a given size-of ball so that their points I) do not at the centre when cldsed and-by making the other two point of junction. In order to prevent this it has been found necessary in manufacture to place a short plastic rubber plug between the pointsofthe plates just as they are closing, this plug providing material for en-, uring a proper joint being made where the mg away with their pointed ends so as to sectional points of the rubber join. This points of the first two plates a when the means for holding the rubber or like sheet inplates shown in the foregoing figures and.

going defects are eliminated in one modifiplates 0 somewhat larger than usual and dolines on which the joints of the rubber leave flat meeting edges d in line with the whole of the four plates are closed, as in Fig. 2. Ne therefore obtain a central joint e in the ball (Fig. 5) having a comparatively long surface which allows the rubber material to be sealed at the edges and at the junction of such edges with the longitudinal joints 1 in a perfectly straight manner without using a separate rubber plug to assist in making the joint.

In a second modification Fig. 4 the upper edges 9 of two of the petal-shaped plates a are curved instead of being pointed and wher. closed leave a considerable space between their extreme edges. In conjunction with two plates at so formed we employ two other plates 0 at right angles to them the edges of which are curved to correspond with those of the first two but to leave a comparatively long straight joint d as before where they meet.

The petal-shaped plates arepivoted at their lower ends to a block h in the known way and are moved about the pivots by links coupled to cars 2' and to slides (not shown) such slides being connected to the operating lever also in the known way.

The foregoing construction of petalshaped plates make admirable joints in the ball structure at the places referred to but to doubly ensure the effectiveness of such joints we may form transverse ribs j on the inside of plates 0 near to the flat meeting edges (Z to assist in holding the rubber sheet in position as the four plates are being closed or to prevent it creeping through the joint at the meeting edges d of plates 0. These ribs also assist in compressing the rubber somewhat as the plates are closed, thus consolidating the joint.

As a. further means of ensuring perfect joints in the rubber material, particularly at the junctions of the ioint e with the longitudinal joints f we fix on the ears 6 pointed memes spurs or plates is, the points. of which project over the aforesaid junctions when the plates are being closed so preventing undue v escape of rubber at these points.

1 Motor horn bulbs and bulbs for syringes at I claim as my invention and desire to secure by Letters Patent is 1. In a ball making machine, four petalshaped rplates arranged in pairs and pivotally connected together at one end, the plates of one pair being longer than the plates of the other pair and being provided with transversely arrangedends which meet together and form a joint when the plates are closed.

2. A ball making machine as set forth in claim 1, the petal-shaped plates being formed with curved interlocking side edges.

3. A ball making machine as set forth in claim 1, the longer petal-shaped plates being provided with ribson their inner faces adjacent to their said transversely arranged ends.

4. A ball'making machine as set forth in I claim 1, the shorter petal-shaped plates being provided with spurs which overlap the end portions of the joint between the said In hand. ALFRED LAWTort 

